1. Field of Invention
The present invention relates to an optical inspection system. More particularly, the present invention relates to a sieving apparatus for sample on a bio-chip.
2. Description of Related Art
A bio-chip is widely used in a biologic inspection system to sieve out the interesting samples. Usually, one sample or various samples arc put on a bio-chip at the detection units, respectively. The detection units on the bio-chip are sieved one by one. The bio-chip is implemented into a detection system for sieving each sample. The detection system is an optical detection system. The sample is illuminated by a light beam generated from a light source. The optical detection system then detects a fluorescent light from the sample on the bio-chip, whereby a particular component content in the sample is detected. As a result, the samples having the particular component are sieved out from the samples pool.
The bio-chip typically includes a specified material at the detection units. Once the samples are put onto the bio-chip, the material reacts with the particular component contained if the detected sample contain the particular component. After reaction, the component becomes fluorescent if the reacted component is illuminated by a light with a specific wavelength. Currently, the bio-chip detection apparatus needs an external light source. The external light source emits a light beam that is incident onto the detection unit of the bio-chip from side. If the fluorescent signal is successfully detected out, the sample is indicated as the sample containing the particular component.
FIG. 1 is a drawing, schematically illustrating a conventional optical detection system for a bio-chip. In FIG. 1, the conventional optical detection system includes an objective lens 100, a slit 102, a filter 104, a photomultiplier tube 106, an electronic filter 108, and a computer 110.
A bio-chip 130 with the sample is illuminated by an argon ion laser beam 150 from side with an incident angle of 45 degrees through a lens 140. The laser beam illuminated the specified sample of the bio-chip 130, then the sample containing the component produces a fluorescent light 120. The fluorescent light 120 goes through the objective lens 100, the slit 102, the filter 104, and then reach the photomultiplier tube 106. The photomultiplier tube 106 amplifies the fluorescent light 120 and convert it into an electronic signal. The electronic signal is exported to the electronic filter 108, and then to the computer 110 for processing.
In the foregoing conventional optical detection system for the bio-chip have to associate with an external light source. The whole system is complex and has a large volume. It is difficult to align and adjust. In this manner, the detection system for bio-chip is installed on a fixed frame only at a medical center or the similar centers. The sample sieving process is always performed at the centers. This causes very inconvenient and inefficient particularly when a large amount of samples need to be sieved.